LTC1435CS Linear Technology, LTC1435CS Datasheet
LTC1435CS
Specifications of LTC1435CS
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LTC1435CS Summary of contents
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... The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 30V (36V maximum). , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation 4.5V TO 28V ...
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... I = 15mA INTVCC EXTVCC I = 15mA, V Ramping Positive INTVCC EXTVCC C = 100pF (Note 4) OSC U W INFORMATION ORDER PART TOP VIEW NUMBER BOOST LTC1435CG LTC1435CS LTC1435IG 5 12 INTV CC LTC1435IS PGND 9 8 EXTV CC S PACKAGE 16-LEAD PLASTIC SO = 125 C, = 130 125 C, = 110 unless otherwise noted. ...
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... ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range. LTC1435CG/LTC1435CS LTC1435IG/LTC1435IS: – Note calculated from the ambient temperature T J dissipation P according to the following formula: D LTC1435CG/LTC1435IG )(130 C/ LTC1435CS/LTC1435IS )(110 C/ TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Input Voltage V = 3.3V OUT 100 ...
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LTC1435 W U TYPICAL PERFORMANCE CHARACTERISTICS Input Supply and Shutdown Current vs Input Voltage 2.5 2 OUT 1.5 EXTV = V CC OUT V = 3.3V 1.0 OUT EXTV = OPEN CC 0.5 SHUTDOWN ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Burst Mode Operation V OUT 20mV/DIV V ITH 200mV/DIV I = 50mA LOAD PIN FUNCTIONS C (Pin 1): External capacitor C OSC ground sets the operating frequency. RUN/SS (Pin 2): Combination of ...
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LTC1435 U U FUNCTIONAL DIAGRA + OV – 1.28V V OSENSE V FB – 1.19V 180k m + – SHUTDOWN RUN 30k SOFT START RUN/SS 3 ...
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U OPERATION (Refer to Functional Diagram) Main Control Loop The LTC1435 uses a constant frequency, current mode step-down architecture. During normal operation, the top MOSFET is turned on each cycle when the oscillator sets the RS latch, and turned off ...
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LTC1435 U U APPLICATIONS INFORMATION The basic LTC1435 application circuit is shown in Figure 1, High Efficiency Step-Down Converter. External compo- nent selection is driven by the load requirement and begins with the selection of R SENSE known, C and ...
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U U APPLICATIONS INFORMATION MOSFET is on. Lower inductor values (higher I cause this to occur at higher load currents, which can cause a dip in efficiency in the upper range of low current operation. In Burst Mode operation, lower ...
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LTC1435 U U APPLICATIONS INFORMATION where is the temperature dependency constant inversely related to the gate drive current. 2 Both MOSFETs have I R losses while the topside N-channel equation includes an additional term for tran- ...
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U U APPLICATIONS INFORMATION INTV Regulator CC An internal P-channel low dropout regulator produces the 5V supply which powers the drivers and internal circuitry within the LTC1435. The INTV CC 15mA and must be bypassed to ground with a minimum ...
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LTC1435 APPLICATIONS INFORMATION + BAT85 N-CH EXTV L1 CC LTC1435 SW BG N-CH PGND Figure 4b. Capacitive Charge Pump for EXTV Topside MOSFET Driver Supply ( external bootstrap ...
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U U APPLICATIONS INFORMATION Foldback Current Limiting As described in Power MOSFET and D1 Selection, the worst-case dissipation for either MOSFET occurs with a short-circuited output, when the synchronous MOSFET conducts the current limit value almost continuously. In most applications ...
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LTC1435 U U APPLICATIONS INFORMATION MOSFET and the synchronous MOSFET. If the two MOSFETs have approximately the same R the resistance of one MOSFET can simply be summed with the resistances of L and R losses. For example, if each ...
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U U APPLICATIONS INFORMATION Design Example As a design example, assume V = 12V(nominal 22V(max 3.3V and f = 250kHz, R OUT MAX and C can immediately be calculated: OSC R = 100mV/3A ...
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LTC1435 U U APPLICATIONS INFORMATION C OSC RUN/ SFB 5 SGND 100pF SENSE 1000pF 8 SENSE U TYPICAL APPLICATIONS C OSC 68pF 1 ...
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U TYPICAL APPLICATIONS C OSC 68pF 1 C OSC RUN/ 10k 330pF 51pF 4 SFB INTV CC 5 SGND 100pF 6 V OSENSE 7 – SENSE ...
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LTC1435 U TYPICAL APPLICATIONS Constant-Current/Constant-Voltage High Efficiency Battery Charger C2* C1 1.5M 35V 35V E3 GND E3 SHDN C12 C13 R5 0.1 F 0.033 F 1k C14 1000pF 100pF U2 ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... High Frequency, Small Inductor, High Efficiency Switchers, 1.5A Switch High Efficiency 5V to 3.3V Conversion 15A Full-Featured Single Controller Full-Featured Dual Controllers 1.3A, Li-Ion, NiCd, NiMH, Pb-Acid Charger 5V Standby in Shutdown 5V Standby in Shutdown LT/GP 0896 7K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1996 V OUT 2.9V/3A C OUT 100 F 10V 2 ...